Fuse-plug



W. COTTRELL.

FUSE PLUG. APPLlcATloN FILED )uu/19.1915.

" f illy Patented Octa 12, 1920.

UNITED STATES PATENT OFFIC.

WILLIAM COTTRELL, OF CHICAGO, ILLINOIS, ASSIGNOR TO BENJAMIN ELECTRIC NOIS.l

FUSE-PLUG.

Application filed July 19,

To all whom t may concern.'

Beit known that I, VILLIAM COTTRELL, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented new and useful Improvements in F use-Plugs, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawing, forming a part of this specification.

My invention relates to fuse plugs, and more specifically to fuse plugs provld-ed with a fuse support or carrier on which are mounted a plurality of fuses which can be successively brought into the circuit.

ne of the objects of my invention is to provide a fuse plug of the character indicated which shall be simple in construction and efficient in operation and easy to manufacture.

Further objects will appear from the detailed description to follow and from the appended claims.-

In the drawings, in which I have shown two embodiments of my invention- Figure 1 is an axial section of a fuse plug showing the circuit;

Fig. 2 is a bottom view of the plug shown in Fig. 1 showing the relative arrangement of the fuses;

Fig. 3 is a section on the line 3-3 of Fig. 1 showing the fuse carrier;

Fig. 4 is a section substantially on the line 4-4 of Fig. 1 showing the spring contact.

The fuse plug here shown comprises a fuse support 34, a plug portion 35 to which the support 34 is non-rotatably secured, a quick-detachable connection 36 betweenhthe plug and support, and a rotatable switch device 37 for successively making connection with the fuses. The plug 35 comprises an insulating base 38 and shell and center contacts 39 and 40 supported thereby. The base 38 has a reduced portion 41 about which the switch device 37 is rotatably mounted and is provided .with a rectangular recess 42 to accommodate the connection 36 and has an axial opening 43 to provide for the electrical and mechanical connection between the plug portion and carrier. The shell contact 39 is reduced, as shown at 44, to provide a contact for the contact carried by the switch device 37. A pin 46 is lo- Specification of Letters Patent.

Patented Oct. 12, 1920. 1915. serial No. 40,673.

cated in the opening 43 and is provided with a shoulder 47 for engagement with a shoulder'48 in the opening 43 and has a screw threaded connection with the center contact 4Q. The lower end of the pin 46 is provided with a rounded head or knob 49 locatedin the recess 42 for engagement with the spring fingers of the U-shaped contact 50 which is connected with the carrier 34 by means of' a bolt or screw 51, the head of which engages a star-shaped plate 52 of conducting material to which the ends of the fuses 17 are electrically connected.

g he fuse carrier or support 34 comprises an insulating base 16 and a plurality of fuses 17 supported by the base and located in curved grooves 18 in the base. Extending through openings 19 in the base are a plurality of hollow rivets or eyelets 20 having their upper ends seated in depressions 21 in the base 16, the outer end of the fuse 17 being connected between these eyelets 20 and the star-shaped plate 52.

The insulating base 16 is provided with a chamber 27 which is closed by means of an insulating transparent plate 28 of mica or other suitable material, through which the fuses 17 are visible. This mica plate 28 is held on the base 16 by means of eyelets 29. The chamber 27 may e made of dilerent sizes to correspond to the capacity of the fuses which are used, a larger fuse necessitating a larger explosion chamber than a smaller one. The depressions 21 into which the contact 54 snaps are each provided with an abrupt edge 30 on the one side (in order that the contact may be suddenly made) and with a slopingedge 31 in order that the carrier 34 may be rotated to bring another fuse into position (the spring contact 54 riding up the sloping edge 31 as the carrier rotates).

The carrier 34 is provided with a flange or skirt portion 32, the thumb-ring 53 being correspondingly recessed to receive the flange 32.

It will be noted that a large chamber 27 1s ing from blowing of the fuses and that these gases can escape through the eyelets 2O and thence through the space between the thumb-ring 53 and insulating base 16. The flange 32 is provided to prevent these escaping gases from burning the fingers of the provided to take care of the gases resultlighter fastening can )ne of the edges 31 may be as after the person who is handling the plug and this makes a tortuous path for the gases and reduces their temperature.

By providing the depressions 21 with one abrupt edge the contact is quickly made thus reventing the contact from being burned. made sloping, fuse is blown there is no current and no danger of arcing as the contact moves away from the eyelet.

The switch device 37 comprises a thumb ring or disk 53 which may have a knurled edge to afford a convenient means grasping, a spring contact tongue 54 located in position to engage the eyelets 20 and having a portion engaging the reduced portion 44 of the shell contact 39, and a hollou7 rivet or eyelet 55 orsecuring the contact 54to the thumb ring. The thumb ring 53 is recessed as shown at 56 to provide for the movement of the contact 54 as it rides up the sloping edge 31 of the recess 21, and is also recessed as shown at 57 to accommodate the flange 32 on the fuse carrier.

It will be noted that the connection between the support 34 and plug portion 35 is such as to prevent relative rotation therebetween, as the rectangular recess 42 (see Fig. 2) will prevent rotation of the U- shaped contact 50 therein and the bolt or screw 51 is drawn tightly enough to prevent relative rotation between the spring contact 50 and the support 34.

It will be observed that the plug portion 35 and the rotatable switch device 37 will not need to be replaced but may be used with the new use support. The circuit through the plug of this modification is from the center Contact 40 through the pin 46, contact 5C, screw 51, plate 52, fuse 17, eyelet 20, and contact 54 to the reduced portion 44 of the shell contact 39.

In using the plug the parts may be assembled as shown in Fig. 1 and the plug portion 35 screwed into the receptacle using the fuse support 34 as a thumb piece. When it is desired to make connection with a new fuse the switch device 37 is rotated by grasping the thumb ring 53, the contact 54 riding up the sloping side 31 of the depression 21 and then snapping down off of the abrupt edge 30 of the succeeding depression 21 into contact with the upper end of the eyelet 20.

The shape of the recesses 21 not only permits a contact to be made quickly and enables the spring contact 54 to ride out of the recesses but also prevents relative rotation between the spring contact 24 and the fuses in the wrong direction.

The fact the the gases can escape easily from the chamber 27 through the eyelets 20 lessens the strain on the eyelets 29 which hold the mica plate 28 in place so that a be used for the mica plate than would otherwise be the case.

for

The use of the eyelets 29 for holding the mica plate in position eliminates the necessity or using a sheet metal cap, now commonly used Jfor this purpose.

It will be noted that all of the fuses are located in a common chamber which enables the chamber to be made much smaller than would be the case if an individual chamber were provided for each fuse.

Having thus described my invention what- I claim as new and desire to secure by Letters Patent is 1. A multiple fuse plug comprising a plug portion having contacts or engaging the contacts of a receptacle, a fuse support nonrotatably mounted with respect to vsaid plug portion, a plurality of fuses supported thereby, and means including a member mounted to rotate with respect to said plug portion when the plug' is in position in the receptacle for successively making connection with said fuses, said rotatable member being mounted to rotate about the-axis of said plug and being held between said plug and support.

2. A multiple fuse plug comprising a plug portion having contacts for engaging the contacts of a receptacle, a fusev support non-rotatably mounted with respect to said plug portion, a plurality of fusessupported thereby, and means including a member mounted to rotate with respect to said plug portion when the plug is in position in the receptacle for successively malng connection with said fuses, said rotatable member being mounted to rotate about the axis of said plug and being and` support, said support having a face on the side toward the plug, contacts on said face connected with said Jfuses, and a spring contact on said rotatable member for engaging the contacts on the support. l

3. A multiple fuse plug comprising a plug portion having contacts for engaging the contacts of a receptacle, a fuse lsupport nonrotatably mounted with respectrto said plug portion, a plurality of fuses supported thereby, means including a member mounted to rotate with respect to said plug portion for successively making connectionv with said fuses, and means for preventing axial movement of said rotatable'member with respect to said plug, said Jfuse support being roheld between said plug Y tatable without withdrawingsaid plug porthe base, and said rotatable member being provided With a Contact for engaging said extended portion ofthe shell Contact.

5. A multiple fuse plug comprising a plug-in portion having shell and center contacts for engagement With the contacts of `a receptacle, a plurality of fuses, and a fusec'arrier for said fuses, said shell contact belng provided with an annular reduced portion. and a Contact member rotatably mounted With respect to said reduced portion and electrically connected therewith, for bringing the different fuses into electrical connection With said shell and center contacts.

Inwtness whereof, I have hereunto subscribed my name.

WILLIAM COTTRELL. 

